Occlusive Chest Wound Seal with a One-Way Vent for Preventing and Treating Tension Pneumothorax

ABSTRACT

A vented chest wound seal for a penetrating chest wound including a flexible sheet including a bottom surface, and an adhesive layer covering a portion of the bottom surface of the flexible sheet, the adhesive layer including an inner perimeter and an outer perimeter, the inner perimeter defining a chamber, wherein the chamber includes a vent channel extending radially outward from a central portion of the chamber, wherein the flexible sheet includes a vent hole aligned over the vent channel, and wherein the inner perimeter and the outer perimeter are separated by a minimum hydrogel width.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application incorporates by reference and claims the benefit ofpriority to U.S. Provisional Patent Application No. 61/989,845 filed May7, 2014, and U.S. Provisional Patent Application No. 62/017,352 filedJun. 26, 2014.

BACKGROUND OF THE INVENTION

The present subject matter relates generally to a chest wound seal forfirst responders. More specifically, the present invention relates to achest wound seal that stores compactly, includes: four-sided sealing; aone-way venting valve with no rigid components; and a one-way valve andvent channel resistant to blockage from clotting; and, additionally, achest wound seal that may be thin; flexible; conformal to body contours;aggressively adhesive to contaminated surfaces (stick and stay); highlyresistant to externally-originated particulate contamination; functionalwhen covered with patient's clothing; and configurable as venting ornon-venting.

When an individual suffers a puncture wound to the chest, such as frombeing shot or stabbed, the wound often penetrates into the chest cavityso as to puncture the parietal pleura, visceral pleura, and sometimeseven the lungs. Such a wound allows air to flow freely through the openchest wound into the chest cavity and pleural space each time thepatient breathes.

The condition wherein air penetrates into the pleural space between thelung and the chest wall through a wound hole in the chest wall is anopen pneumothorax. When an open pneumothorax occurs, the normalmechanism by which the lung expands is lost; i.e., the fluid adhesion ofthe pleural surface of the lung to the pleural surface of the chestwall. Thus, the affected lung does not expand normally when the patientinhales.

A tension pneumothorax can occur when a one-way valve is formed by thewound that allows airflow into the pleural space while preventingairflow out. In a tension pneumothorax, each inhalation traps air in thechest, increasing pressure on the lungs and ultimately causing them tocollapse. Additionally, the increasing pressure pushes important organs,such as the heart, major blood vessels, and airways, toward the centerof the chest. This shifting can cause further compression of the lungsand may affect the flow of blood returning to the heart. Theseadditional complications in a tension pneumothorax make it a lifethreatening condition that requires immediate treatment.

For patients with an open wound to the chest, the severity of the openpneumothorax that develops can be minimized by sealing the open woundvia an occlusive bandage. For proper sealing, the bandage must be air-and liquid-tight, must be flexible enough to conform to all bodycontours, and must have an adhesive strong and persistent enough to keepthe seal in place while subject to patient movement and various bodyfluids. The occlusive bandage may be used to eliminate air penetratinginto the pleural space through the wound hole when the patient inhales.

In addition to developing a tension pneumothorax by air leakage throughthe chest wound, a patient with an open chest wound that is covered byan occlusive chest bandage may also develop a tension pneumothorax in adifferent manner. For instance, the bandage may have eliminated air fromentering the pleural space through the wound hole, yet if lacerated, thelung will continue to leak air into the pleural space. Consequently,every time the patient inhales, more air becomes trapped in the pleuralspace, causing more pressure to be exerted on the lacerated lung. Again,this increased pressure on the lacerated lung forces the lung tocollapse.

To successfully prevent a tension pneumothorax from developing, the airflow into the pleural space via the wound hole must be eliminated, butthe air coming from the lacerated lung must be allowed to escape thepleural space via the wound hole.

Therefore, a need exists for a compact, low profile, adhesive chestwound seal for use by first responders that includes a one-way valvethat ensures effective venting of air and/or other fluids from thepleural cavity during exhalation while sealing a chest wound against airentry during inhalation, without risk of being dislodged duringtreatment of the patient.

U.S. Pat. No. 5,478,333 to Asherman (“Asherman”) discloses a one-wayvalve apparatus installed in a chest wound seal to be used for treatinga tension pneumothorax, as well as treat hemothorax (blood accumulationin the pleural cavity). The adhesive used on Asherman fails when exposedto bodily fluids such as blood or sweat. If the adhesive fails, thenAsherman will not exhibit a 4-sided seal, rendering itsair-ingress-during-inhalation-prevention function useless.

In addition, the design of Asherman will only allow air egress duringexhalation if the valve apparatus is free of encumbrances, such asclothing, impinging on the valve exit end. Such interference will kinkthe valve shut, rendering it inoperative, and thereby turning Ashermaninto a simple occlusive chest wound seal. Further, Asherman will alsonot vent if the patient is lying upon the chest wound/vent, which willalso kink the vent exit. Such a condition will prevent air ingressduring inhalation, but will also prevent air/fluid egress duringexhalation, a situation that can lead to formation of a life-threateningtension pneumothorax.

U.S. Pat. No. 7,504,549 to Castellani et al. (“Hyfin”) discloses aone-way valve fabricated as an integral part of a thin, flexible chestwound seal that claims to prevent tension pneumothorax. Hyfin disclosesthat its drainage channel terminates at the peripheral edge of the chestwound seal. The lack of a full perimeter of adhesive (hydrogel) incombination with a thin and flexible backing sheet can allow the Hyfinto fold along its drainage channel and allow the two sides of thatchannel to contact each other during Hyfin application, causing thechannel to close upon itself. The hydrogel is aggressively sticky, andonce stuck to itself, cannot easily be separated to reopen the occlusionin the channel.

U.S. Pat. No. 7,834,231 to Biddle et al. (“Biddle”) discloses aplurality of one-way valve apparati installed in a thin, flexible chestwound seal that claims to prevent tension pneumothorax. Biddle containsa one-way valve with a fibrous filter in line with the air flow path.The limited clear egress fluid path will be prone to blockage if theblood from the chest wound clots. Clotting will render Biddle a simpleocclusive chest wound seal.

In addition, the one-way valve mechanism is subject to interference byexternally originated particulate contamination, which can prevent valveclosure during inhalation. If a valve fails to seal during inhalation,air can enter the pleural space through the chest wound and cause theformation of a life-threatening tension pneumothorax.

U.S. Pat. Appl. No. US 2012/0046582 to Hopman et al.(“Hopman”)—discloses a one-way valve apparatus installed in a chestwound seal that claims to prevent tension pneumothorax. The Hopman valveis a rigid, bulky one-way valve apparatus. The Hopman valve issusceptible to externally originated particulate contamination, whichcan prevent valve closure during inhalation. If the valve fails to sealduring inhalation, air can enter the pleural space through the chestwound and cause the formation of a life-threatening tensionpneumothorax.

The one-way valve can be protected from external contaminants byreplacing its removable cover, but with the cover in place, the vent isrendered inoperative, thereby turning Hopman into a simple occlusivechest wound seal. Such a condition will prevent air ingress duringinhalation, but will also prevent air/fluid egress during exhalation, asituation that can lead to formation of a life-threatening tensionpneumothorax.

In addition, the rigid, bulky one-way valve apparatus of Hopmanprotrudes approximately ⅝ of an inch above the top surface of the chestwound seal. This bulkiness ensures that fewer of the units can becarried in first responder kits than other thinner, more flexible chestwound seals.

Accordingly, there is a need for a chest wound seal for first respondersthat stores compactly, includes: four-sided sealing; a one-way ventingvalve with no rigid components; and a one-way valve and vent channelresistant to blockage from clotting; and, additionally, is thin;flexible; conformal to body contours; aggressively adhesive tocontaminated surfaces (stick and stay); highly resistant toexternally-originated particulate contamination; functional when coveredwith patient's clothing; and configurable as venting or non-venting, asdescribed herein.

BRIEF SUMMARY OF THE INVENTION

To meet the needs described above and others, the present disclosureprovides a chest wound seal for first responders that stores compactlyand includes: four-sided sealing; a one-way venting valve with no rigidcomponents; and a one-way valve and vent channel resistant to blockagefrom clotting. Additionally, the present disclosure provides a chestwound seal for first responders that is: thin; flexible; conformal tobody contours; aggressively adhesive to contaminated surfaces (stick andstay); highly resistant to externally-originated particulatecontamination; functional when covered with patient's clothing; andconfigurable as venting or non-venting.

The present invention satisfies the objectives by providing a chestwound seal that is an occlusive dressing for use on a penetrating chestwound that may be used to treat an open pneumothorax and/or to prevent atension pneumothorax. The chest wound seal contains a one-way valve thatallows air and/or other fluids to exit the pleural space duringexhalation but blocks air from entering the pleural space duringinhalation. The chest wound seal, by the inclusion of these twofunctions of the one-way valve, may be used to treat an openpneumothorax and prevent a tension pneumothorax.

The chest wound seal may include several thin layers in a novelarrangement that together become an integrated one-way valve thatensures effective venting of air and/or other fluids from the pleuralcavity. The chest wound seal may be thin to render it unobtrusive duringuse on a patient. The thinness also enables a low-volume package, whichallows many units to be carried in a small volume. The chest wound sealmay also include an integrated one-way valve that may be resistant tothe effects of externally originated particulate contamination, whichensures the aforementioned effective venting of air or other fluids fromthe pleural cavity during exhalation and reliable sealing against airingress during inhalation.

The chest wound seal uses an aggressively sticky hydrogel as itsadhesive, which exhibits excellent adhesion properties even on surfacesthat are contaminated with blood, hair, or other bodily fluids. Thestrong adhesion minimizes the risk of the chest wound seal beingdislodged during treatment or movement of the patient.

The chest wound seal's one-way valve doesn't protrude above the topsurface of the chest wound seal, which helps ensure that it willfunction correctly when covered with the patient's clothing.

The chest wound seal employs no fibrous filters in the vent path, whichreduces the likelihood of blockage due to clotting at the filter.

The chest wound seal's one-way valve employs a large sealing surfacethat contains no rigid components. This feature of the chest wound sealrenders it highly resistant to interference from externally originatedparticulate contamination, which ensures that it will function correctlyin the presence of said particulate contamination.

The chest wound seal includes a vent channel that does not require theundesirable elimination of the adhesive hydrogel at the peripheral edgeof the chest wound seal. The unique design of the vent permits hydrogeladhesive to completely surround the chest wound, thereby providing afull 360-degrees sealing, or a “four-sided” seal. The presence ofadhesive gel all the way around the chest wound seal's perimeter alsoprovides added rigidity in the area of the vent channel duringapplication to the patient. That added rigidity reduces the likelihoodof accidental folding of the chest wound seal along its vent channel,having the two sides of the channel touch and stick together, andblocking the channel.

One embodiment of the chest wound seal includes a removable adhesivemember that blocks the vent opening. That blocking member is intendedfor use when a non-vented chest wound seal is desired. The blockingmember may be only a few mils thick, and when present is unobtrusive andflexible. Its presence does not add bulk to the chest wound seal. Thatlack of additional bulk allows the use of the same small packaging,ensuring that more of the units can be carried in first responder kitsthan other thicker, less flexible chest wound seals.

In one embodiment, the chest wound seal includes: a thin, flexible,plastic backing sheet; an adhesive sheet with an inner perimeterdefining a chamber and a channel; and a vent hole in the thin, flexibleplastic sheet. To enable use of the chest wound seal, the chest woundseal includes: a lifting tab integral with the thin plastic sheet; arelease strip on an edge of the adhesive sheet at a base of a liftingtab; and a release liner to be removed before application.

Optionally, the chest wound seal may include a removable adhesive venthole cover that blocks the vent exit, thereby establishing the initialconfiguration of the chest wound seal as a non-vented chest wound seal.Removal of the adhesive vent hole cover converts the non-vented chestwound seal into a vented chest wound seal, with all the aforementionedbenefits of a vented chest wound seal.

The chest wound seal may come packaged in a sealed, vacuum-packed,plastic envelope that may be sterile. The flatness and flexibility ofthe package and the chest wound seal, allow the packaged chest woundseal to be folded or rolled to allow storage in a small space.Alternatively, the chest wound seal may be distributed in bulkunpackaged and unsterilized.

To use the chest wound seal the user must tear open the sealed,vacuum-packed, sterile plastic envelope, if so packaged, and remove thechest wound seal. If the chest wound seal is folded inside thepackaging, it must be unfolded. The user must locate the chest wound onthe patient. If possible, the user should clean the area around thechest wound at least four inches from the wound of blood, sweat, dirt,and any loose debris, in order to ensure adequate adhesion of the chestwound seal. After the wound is cleaned the user must grasp the liftingtab with one hand and remove and discard the removable release linerfrom the chest wound seal with the other hand. The chest wound seal mustbe applied over the patient's wound, adhesive side down, centered overthe wound.

Once applied, the one-way valve contained in the chest wound sealoperates as described to permit venting through the penetrating chestwound of air and/or other fluids from the pleural space duringexhalation, thereby preventing tension pneumothorax. During inhalation,the one-way valve contained in the chest wound seal blocks air fromentering the pleural space via the penetrating chest wound.

In an embodiment, a vented chest wound seal for a chest wound includes:a flexible sheet including a bottom surface; and an adhesive layercovering a portion of the bottom surface of the flexible sheet, theadhesive layer including an inner perimeter and an outer perimeter, theinner perimeter defining a chamber; wherein the chamber includes a ventchannel extending radially outward from a central portion of thechamber, wherein the flexible sheet includes a vent hole aligned overthe vent channel, and wherein the inner perimeter and the outerperimeter are separated by a minimum hydrogel width.

In an embodiment, the chest wound seal further includes: a lifting tabintegrally formed with the flexible sheet; a plastic support sheetsecured to the lifting tab to provide support; and a narrow releasestrip applied over a bottom surface of an edge of the adhesive layerclosest to the lifting tab.

In an embodiment, the chest wound seal further includes: a lifting tabintegrally formed with the flexible sheet; a plastic support sheetsecured to the lifting tab to provide support; wherein a portion of theplastic support sheet is applied over a bottom surface of an edge of theadhesive layer closest to the lifting tab.

In an embodiment, the chest wound seal further includes a vent holecover, wherein the vent hole cover includes an adhesive surface and apull tab, wherein the adhesive surface secures the vent hole cover overthe vent channel. In some embodiments, the chamber further includes asecond vent channel extending radially outward from the central portionof the chamber, wherein the flexible sheet includes a second vent holealigned over the second vent channel. And, in some embodiments, thechamber further includes a third vent channel and a fourth vent channelextending radially outward from the central portion of the chamber,wherein the flexible sheet includes a third vent hole aligned over thethird vent channel, and a fourth vent hole hold aligned over the fourthvent channel.

In some embodiments, the vent channel extends a length from a center ofthe chamber to a terminus, wherein a shape of the terminus of the ventchannel is approximately semi-circular. Additionally, in someembodiments, a length from a center of the chamber to a center of thevent hole is in the range of one to two and a half inches. Also, in someembodiments, the length from the center of the chamber to the center ofthe vent hole is in the range of one and one fourth inches to twoinches. Further, in some embodiments, the length from the center of thechamber to the center of the vent hole is approximately one and a halfinches.

In some embodiments, the minimum hydrogel width is one-half inch orgreater. And, in some embodiments, the minimum hydrogel width isapproximately one-inch. Further, in some embodiments, the vent channelis approximately three-fourths of an inch wide.

Some objects of the invention are to provide a chest wound seal forfirst responders that is: thin; flexible; and conformal to bodycontours.

Additional objects of the invention are to provide a chest wound sealfor first responders that includes four-sided sealing; is highlyresistant to externally-originated particulate contamination; isfunctional when covered with patient's clothing; is configurable asventing or non-venting; and stores compactly.

Further objects of the invention are to provide a chest wound seal forfirst responders that includes aggressive adhesion to contaminatedsurfaces (stick and stay); includes a one-way venting valve with norigid components; and includes a one-way valve and vent channelresistant to blockage from clotting.

Additional objects, advantages and novel features of the examples willbe set forth in part in the description which follows, and in part willbecome apparent to those skilled in the art upon examination of thefollowing description and the accompanying drawings or may be learned byproduction or operation of the examples. The objects and advantages ofthe concepts may be realized and attained by means of the methodologies,instrumentalities and combinations particularly pointed out in theappended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawing figures depict one or more implementations in accord withthe present concepts, by way of example only, not by way of limitations.In the figures, like reference numerals refer to the same or similarelements.

FIG. 1 illustrates an exploded isometric view of the vented chest woundseal that is one embodiment of the chest wound seal disclosed herein.

FIG. 2A illustrates a top plan view of one embodiment of the chest woundseal showing the orientation angle between the vent channel and thelifting tab. The optional vent hole cover is removed in order to clearlyshow the vent channel and vent hole.

FIG. 2B illustrates a top plan view of an alternate embodiment of thechest wound seal showing a different orientation angle between the ventchannel and the lifting tab. The optional vent hole cover is removed inorder to clearly show the vent channel and vent hole.

FIG. 2C illustrates a top plan view of another alternate embodiment ofthe chest wound seal showing two vent channels and other differentorientation angles between the vent channels and the lifting tab. Theoptional vent hole covers are removed in order to clearly show the ventchannels and vent holes.

FIG. 2D illustrates a top plan view of another alternate embodiment ofthe chest wound seal showing four vent channels. The optional vent holecovers are removed in order to clearly show the vent channels and ventholes.

FIG. 3A illustrates an isometric view of the chest wound seal applied toa penetrating chest wound and allowing air and/or other fluids to ventfrom the wound through the open one-way valve during exhalation.

FIG. 3B illustrates an isometric view of the chest wound seal applied toa penetrating chest wound and preventing air from entering the woundthrough the closed one-way valve during inhalation.

FIG. 4A illustrates a sectional view at an enlarged scale taken alongLine 4A-4A of FIG. 3A.

FIG. 4B illustrates a sectional view at an enlarged scale taken alongLine 4B-4B of FIG. 3B.

FIG. 5A illustrates a sectional view, not to scale, with some detailsenlarged to show their details, taken along Line 5A-5A of FIG. 1.

FIG. 5B illustrates a sectional view, not to scale, with some detailsenlarged to show their details, taken along Line 5B-5B of FIG. 1.

FIG. 6 illustrates an exploded isometric view of another example of avented chest wound seal.

FIG. 7 illustrates a sectional view, not to scale, with some detailsenlarged to show their details, taken along Line 7-7 of FIG. 6.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 illustrates an exploded isometric view of an example vented chestwound seal 100. FIG. 6 illustrates an exploded isometric view of anotherexample of the chest wound seal 100. FIG. 5A is a sectional view, not toscale, with some details enlarged to show their details, taken alongLine 5A-5A of FIG. 1. FIG. 5B is a sectional view, not to scale, withsome details enlarged to show their details, taken along Line 5B-5B ofFIG. 1.

With reference to FIG. 1, FIGS. 5A and 5B, a chest wound seal 100 foruse as an occlusive dressing for a penetrating chest wound is shown. Inan embodiment, the chest wound seal 100 may include a thin, flexiblebacking sheet 10 with a layer of hydrogel adhesive, referred to hereinas a hydrogel adhesive sheet 11, covering a portion of a bottom surface25 of the backing sheet 10. The adhesive sheet 11 may include an innerperimeter 26 and an outer perimeter 27. The inner perimeter 26 maydefine a chamber 12 and a vent channel 13 that lack hydrogel adhesive. Avent hole 14 may be included in the backing sheet 10 and may be alignedwith the end geometry of the vent channel 13. The thin, flexible backingsheet 10, hydrogel adhesive sheet 11, chamber 12, vent channel 13, andvent hole 14 constitute a one-way valve of the chest wound seal 100 topermit air and/or other fluids 22 (FIG. 4A) to exit a penetrating chestwound 20 (FIG. 3A) during exhalation.

As described below with reference to FIGS. 3A-4B, the chamber 12 may beadapted to be centered and placed over the penetrating chest wound 20.The thin flexible backing sheet 10 may be transparent so that thechamber 12 of the chest wound seal 100 may be positioned centered overthe penetrating chest wound 20 and so that the open chest wound 20 maybe visually monitored. A larger chamber 12 makes it easier for the firstresponder to properly position the chamber 12 over the chest wound 20.In an embodiment, the chamber 12 is in the range of one inch to twoinches in width. In a preferred embodiment, the chamber is a squareapproximately two inches wide. In other embodiments, the chamber 12 maybe different sizes or shapes in order to accommodate differentfunctional requirements.

The backing sheet 10 may be impermeable to air and water-based liquids,and should conform and seal over and around debris and irregularities onits mounting surface. Accordingly, it has been observed that flexibilityand conformability are the key characteristics to consider for theflexible backing sheet 10. Maximizing these two characteristics providesoptimal operation of the one-way valve. In an embodiment, the flexiblebacking sheet 10 includes urethane. In other embodiments, other flexibleplastics or similar materials may be used, as will be apparent to thoseof skill in the art from the disclosure herein.

It has been observed that the hydrogel of the adhesive sheet 11 shouldbe as sticky as possible in order to adhere to skin that may becontaminated with blood, sweat, dirt or hair. In an embodiment, theadhesive sheet 11 is constructed from hydrogel adhesive soldcommercially as KM10E Katecho Gel, 0.032″ by Katecho, Inc. of DesMoines, Iowa. In other embodiments, other hydrogel adhesives may be usedas will be appreciated by those skilled in the art from the examplesprovided herein.

The chest wound seal 100 may also include the adhesive-backed plasticsupport sheet 15 that may be to be used to provide support to a liftingtab 19, a narrow strip of plastic sheet that may be used as a releasestrip 16, an adhesive-backed vent hole cover 17, and an additionalplastic sheet that may be used as a removable release liner 18. Thelifting tab 19 may be provided in the shape of a square, semicircle,rectangle, triangle, etc. In an embodiment, the lifting tab 19 isrectangle integrally formed with the backing sheet 10 and is of a sizethat can be gripped by at least two fingers. In a preferred embodiment,the lifting tab 19 is rectangular at two and three-fourths inches wideby one and a half inches deep. These dimensions are considered largeenough to enable grasping by any of the several tested one-handedmethods using either a thumb or heel of the hand and one, two, three, orfour fingers.

The adhesive backed vent hole cover 17 may include a strip of plasticincluding an adhesive portion and a non-adhesive portion. The adhesiveportion may secure the vent hole cover 17 to the backing sheet 10 whilethe non-adhesive portion acts as a pull-tab 31 that may be used forremoval of the vent hole cover 17. Removal of the vent hole cover 17converts the chest wound seal 100 from a non-vented occlusive chestwound seal 100 into a vented occlusive chest wound seal 100 that may besuitable for treatment of an open pneumothorax and prevention of atension pneumothorax. In embodiments including a plurality of vent holes14, a plurality of vent hole covers 17 may be provided to cover eachvent hole 14. Alternatively, in some embodiments, a single vent holecover 17 may cover a plurality of vent holes 14.

The vent channel 13 provides separation between the chamber 12 and thevent hole 14. If the vent hole 14 is positioned over the chest wound 20,the vent hole 14 will prevent the sealing of the flexible backing sheet10 against the patient's chest 21. A longer vent channel 13 willminimize the likelihood of this occurrence. A vent channel length of thevent channel 13 extends from a central portion 28 of the chest woundseal 100 to a terminus 30.

In an embodiment, a possible range for vent channel length is one inch(providing the maximum minimum hydrogel width 29 between the innerperimeter 26 and the outer perimeter 27 at the cost of a high danger ofnon-sealing due to poor placement of the chamber 12) to two and a halfinches (maximum vent hole separation while reducing the minimum hydrogelwidth 29 to a sliver). In other embodiments, the vent channel length isat least one-and-one fourth inches or greater to two inches. In apreferred embodiment, the vent channel 13 is approximately one and onehalf inches long, which is a compromise between the risk of non-sealingand providing an adequate minimum hydrogel width 29 of the adhesivesheet 11. The minimum hydrogel width 29 ensures a strong and persistent360-degrees seal around the penetrating chest wound 20 to minimize therisk of the chest wound seal 100 being dislodged during treatment ormovement of the patient.

The width of the vent channel 13 may also be adapted to improve venting.A wide vent channel 13 allows air to vent easily with minimalbackpressure produced. A wide vent channel 13 is also more tolerant ofclotting, which will narrow the channel width and impede airflow. In anembodiment, the vent channel 13 is approximately three-fourths of aninch wide, which is three times the size of the vent hole 14.Accordingly, clotting would have to reduce the vent channel bytwo-thirds (a reduction of a half-inch) before the venting function isaffected.

The vent channel 13 is superior to prior approaches. For example, unlikeprior chest wound seals with a drainage channel that terminates at theperipheral edge of the chest wound seal, the chest wound seal 100includes adhesive gel along the full perimeter of the backing sheet 10(with the exception of the lifting tab 19). A drawback of the drainagechannel chest wound seals is the risk of the two sides of the channelcreeping or migrating towards each other, pinching off the flow of theair and/or other fluids 22. An advantage of the present chest wound sealis that the geometry of the vent channel 13 (such as its semi-circularshape), as defined by the hydrogel of the adhesive sheet 11, keeps thewalls of the vent channel 13 separated, reducing the likelihood of thechannel walls touching each other, sticking together, and becomingblocked.

Additionally, the drainage channel chest wound seals, with no gel alongthe channel axis, have a gel-free path all the way to the perimeter ofthe seal, greatly increasing the likelihood that the seal will fold atthe channel and stick to itself. The hydrogel at the terminus 30 (FIGS.2A and 2B) of the vent channel 13 of the disclosed chest wound seal 100provides added chest wound seal rigidity, which reduces the likelihoodof inadvertent folding.

With reference to FIGS. 2A, 2B, 2C, and 2D some alternate embodimentsare shown. The alternate embodiments show some possible orientationangles between the vent channel 13 and the lifting tab 19 along withvariation in the number of vent channels 13. In each embodiment thechamber 12 and vent channel 13 are defined by the removal of or absenceof hydrogel adhesive in the adhesive sheet 11. In each of theembodiments the vent channel 13 extends radially outward from a centralportion 28 of the chamber 12, an arrangement that may be the optimumarrangement for the venting of air and/or other fluids 22 from thepenetrating chest wound 20 through the vent hole 14.

FIG. 2A is a top plan view of one embodiment of the chest wound seal 100showing the orientation angle between the vent channel 13 and thelifting tab 19. The vent hole cover 17 may be removed in order toclearly show the vent channel 13 and vent hole 14. As shown, the ventchannel 13 extends radially outward from a central portion 28 of thechamber 12 to the terminus 30. The chamber 20 and the vent channel 13are defined by the inner perimeter 26 of the adhesive sheet 11. Theportion of the adhesive sheet 11 from the terminus 30 to the outerperimeter 27 may be a minimum hydrogel width 29 to provide stability tothe chest wound seal 100. A wider minimum hydrogel width 29 is desiredto maximize perimeter adhesion. In an embodiment, to provide stabilityto the adhesive sheet 11, the minimum hydrogel width 29 is one-half inchor greater. In an embodiment, to provide a sufficient trade-off betweenthe length of the vent channel 13 and the stability of the chest woundseal 100, the minimum hydrogel width 29 is approximately one-inch.

FIG. 2B is a top plan view of an alternate embodiment of the chest woundseal 100 showing a different orientation angle between the vent channel13 and the lifting tab 19. No vent hole cover 17 is shown in thisembodiment. In a preferred embodiment of the chest wound seal 100 shownin FIG. 2B, no vent hole cover 17 is provided.

FIG. 2C is a top plan view of another alternate embodiment of the chestwound seal 100 showing two vent channels 13 and other differentorientation angles between the vent channels 13 and the lifting tab.Similarly, FIG. 2D is a top plan view of another alternate embodiment ofthe chest wound seal 100 showing four vent channels 13 and otherdifferent orientation angles between the vent channels 13 and thelifting tab 19. In this embodiment, the vent channels 13 form a crosspattern. More vent channels 13 provides redundant venting in case one ortwo vent channels 13 become blocked. It is contemplated that the chestwound seal 100 may have as many as eight vent channels 13 and stillfunction properly. In an embodiment, the chest wound seal 100 includesfour channels because more than four vent channels 13 offers diminishingreturns to redundancy.

With reference to FIG. 3A and FIG. 4A, the one-way valve of the chestwound seal 100 is shown in its venting state. FIG. 3A illustrates anisometric view of the chest wound seal 100 applied to a penetratingchest wound 20 and allowing air and/or other fluids to vent from thechest wound 20 through the vent hole 14 during exhalation. FIG. 4Aillustrates a sectional view at an enlarged scale taken along Line 4A-4Aof FIG. 3A. Chamber 12 and vent channel 13 are in an open position, withthe thin, flexible backing sheet 10 shown as pushed away from thesurface of the patient's chest 21 by air and/or other fluids 22 exitingthe penetrating chest wound 20 during exhalation. The exhaled air and/orother fluids 22 are flowing outward in the direction shown by the flowarrow 23 from the penetrating chest wound 20 through the chamber 12 andvent channel 13 and exiting through the vent hole 14. The exiting of airand/or other fluids through the one-way valve results in the treatmentand reduction in severity of the tension pneumothorax condition.

With reference to FIG. 3B and FIG. 4B, the one-way valve of the chestwound seal 100 is shown in its closed state. FIG. 3B illustrates anisometric view of the chest wound seal 100 applied to a penetratingchest wound 20 and preventing air from entering the wound 20 through theclosed one-way valve during inhalation. FIG. 4B illustrates a sectionalview at an enlarged scale taken along Line 4B-4B of FIG. 3B. Chamber 12and vent channel 13 are in a closed position, with the thin, flexiblebacking sheet 10 shown as pushed against the surface of the patient'schest 21 by outside air pressure 24 in response to the negative pressureproduced by the patient's lungs during inhalation. The negative pressureis applied to the chamber 12 and vent channel 13 via the penetratingchest wound 20. When the patient changes from exhalation to inhalationthe air flow through the one-way valve changes direction and thenegative pressure forces the thin, flexible backing sheet 10 to collapseagainst the surface of the patient's chest 21, thereby sealing thepenetrating chest wound 20 in an air tight formation and therebypreventing outside air from entering the patient's pleural space via thepenetrating chest wound 20. In an embodiment, the thin, flexible backingsheet 10 is sufficiently compliant that it may also create a functionalseal in the presence of small airborne debris on the surface of thepatient's chest 21. This tolerance for debris enhances the value of thechest wound seal 100 under conditions where airborne debris is common.The blocking by the one-way valve of outside air from entering thepleural space via the penetrating chest wound 20 results in theprevention of or reduction in severity of the tension pneumothoraxcondition.

In some embodiments, the chest wound seal 100 may be square instead ofround or may be of any appropriate shape necessary for implementing theaforementioned objectives of the chest wound seal 100. In someembodiments, the chest wound seal 100 may be of any appropriate sizethat provides sufficient adhesive area for securely attaching the chestwound seal 100 to the patient. In some embodiments, the chest wound seal100 may have one or more vent channels 13. In some embodiments, thechest wound seal 100 may have vent channels 13 at any appropriateorientation angle between the vent channel 13 and the lifting tab 19.

In some embodiments, the vent hole 14 may be of an appropriate size toaccommodate the air/fluids necessary. A larger vent hole 14 affordsbetter venting efficiency. However, a vent hole 14 that is too large mayaffect the strength of the thin, flexible backing sheet due to theamount of material removal. Additionally, a large vent hole 14 could getcaught on external items due to its large open area. In an embodiment,the vent hole 14 is approximately one fourth of an inch in width ordiameter.

In some embodiments, the vent hole cover 17 may be of any appropriateshape necessary to block the vent hole. In some embodiments, the venthole cover 17 may be of any appropriate configuration that is easilyremoved when necessary. In some embodiments, the chest wound seal 12 mayinclude two lifting tabs 19. And, in some embodiments, the hydrogeladhesive sheet 11 may be any other suitable adhesive.

With reference to FIG. 6 and FIG. 7, another embodiment of chest woundseal 100 for use as an occlusive dressing for a penetrating chest wound20 is shown. The chest wound seal 100 may include four vent holes 14 topermit sufficient venting. In the embodiment shown, the vent holes 14may be arranged in a cross pattern with one of the vent holes 14oriented toward the lifting tab 19.

In the embodiment shown in FIGS. 6 and 7, the release strip 16 has beeneliminated. The adhesive-backed plastic support sheet 15 has applied,adhesive side up, to the bottom surface of the adhesive sheet 11 and tothe bottom surface of the lifting tab 19. The adhesive sheet 11 overlapsthe plastic support sheet 15 an appropriate distance. In one embodiment,the overlap is one-quarter inch. In the absence of the plastic supportsheet 15, when force is applied to the lifting tab 19, the adhesivesheet's adherence to the patient's chest 21 may be stronger than it'sadherence to the backing sheet 10 causing the backing sheet 10 and theadhesive sheet to separate. Accordingly, by attaching the plasticsupport sheet 15 to the adhesive sheet 11 and the lifting tab 19, theplastic support sheet 15 assists in the removal of the adhesive sheet 11during the removal of the chest wound seal 100 from the patient's chest21 by encouraging the separation of the adhesive sheet 11 from thepatient's chest 21.

The chest wound seal 100 may be fabricated using the elements shown inthe exploded view of FIG. 1. The following fabrication sequence is onepreferred method. Other fabrication sequences may be followed if theassembly equipment is capable of maintaining the proper alignmentbetween each of the elements of the chest wound seal 100.

First, as shown in the embodiments shown in FIGS. 1 and 6, a thin layerof hydrogel adhesive sheet 11 gets modified to remove hydrogel from thecutout area that will be used as the chamber 12 and the vent channels13. The hydrogel adhesive sheet 11 may be cut to the generally roundchest wound seal 100 shape or that cut may be made later.

Second, as shown in FIG. 6, the hydrogel adhesive sheet 11 gets appliedto the bottom surface of the thin, flexible backing sheet 10.

Third, in the embodiment shown in FIG. 6, the adhesive-backed plasticsupport sheet 15 gets applied, adhesive side up, to the bottom surfaceof the hydrogel adhesive sheet 11 and to the bottom surface of thelifting tab 19. The hydrogel adhesive sheet 11 will overlap the liftingtab 19 an appropriate distance. In one embodiment, the overlap isone-quarter inch.

To fabricate the embodiment shown in FIG. 1, an alternate fabricationsequence is provided after the hydrogel adhesive sheet is modified toremove hydrogel from the cutout area. The alternate fabrication sequencereplaces the second and third steps above. First, the adhesive-backedplastic support sheet 15 gets applied, adhesive side up, to the bottomsurface of the lifting tab 19 of the flexible backing sheet 10. Next,the hydrogel adhesive sheet 11 gets applied to the bottom surface of thethin, flexible backing sheet and the bottom surface of theadhesive-backed plastic support sheet 15. The hydrogel will overlap theplastic support sheet 15 an appropriate distance. In one embodiment theoverlap is one-quarter inch. Next, the narrow strip of plastic sheetthat will be used as a release strip 16 gets applied over the bottomsurface of the edge of the hydrogel adhesive of the adhesive sheet 11where the hydrogel overlaps the lifting tab 19.

Fourth, in the embodiments shown in FIGS. 1 and 6, the vent holes 14 getcut in the thin, flexible plastic sheet 11, with the center of the ventholes 14 nominally coincident with the center of curvature of thehalf-round hydrogel cutout at the end of the vent channels 13. The ventholes 14 may be cut before the hydrogel adhesive sheet is applied, ifthe fabrication equipment is capable of maintaining the proper alignmentbetween the hole and the hydrogel adhesive cutout of the vent channel13.

Fifth, in the embodiments shown in FIGS. 1 and 6, the plastic sheet thatwill be used as the removable release liner 18 gets applied to thebottom surface of the hydrogel adhesive sheet 11.

If a different fabrication sequence is followed, the vent holes 14 maybe cut after the addition of the removable release liner 18. In thiscase, the cutting of the vent holes 14 may also cut a like hole in theremovable release liner 18.

Next, if the vent hole covers 17 are to be included, the vent holecovers 17 get added to the top surface of the thin, flexible backingsheet 10, in a location sufficient to block the vent holes 14.

Finally, the assembled chest wound seal 100 gets cut to the desiredexterior dimensions. In some embodiments, each of the various layers andcomponents of the chest wound seal 100 may be cut prior to assembly, ifthe assembly equipment is capable of maintaining the proper alignmentbetween all of the layers and components.

The chest wound seal 100 is described using technology and materialsavailable at the time of disclosure. This does not preclude futuretechnological advancements from being included as part of the chestwound seal 100. In language used herein, objects described in thesingular may be provided in the plural and objects described in theplural may be provided in the singular.

The terms, expressions, descriptions, and embodiments employed here areused for purposes of description and illustration and not of limitation.It is to be understood that changes, variations, and alternativeembodiments may be made without departing from the spirit or scope ofthe claims.

It should be noted that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications may be madewithout departing from the spirit and scope of the present invention andwithout diminishing its attendant advantages.

We claim:
 1. A vented chest wound seal for a penetrating chest woundcomprising: a flexible sheet including a bottom surface; and an adhesivelayer covering a portion of the bottom surface of the flexible sheet,the adhesive layer including an inner perimeter and an outer perimeter,the inner perimeter defining a chamber; wherein the chamber includes avent channel extending radially outward from a central portion of thechamber, wherein the flexible sheet includes a vent hole aligned overthe vent channel, and wherein the inner perimeter and the outerperimeter are separated by a minimum hydrogel width.
 2. The chest woundseal of claim 1, further including: a lifting tab integrally formed withthe flexible sheet; a plastic support sheet secured to the lifting tabto provide support; and a narrow release strip applied over a bottomsurface of an edge of the adhesive layer closest to the lifting tab. 3.The chest wound seal of claim 1, further including: a lifting tabintegrally formed with the flexible sheet; a plastic support sheetsecured to the lifting tab to provide support; wherein a portion of theplastic support sheet is applied over a bottom surface of an edge of theadhesive layer closest to the lifting tab.
 4. The chest wound seal ofclaim 1, further including a vent hole cover, wherein the vent holecover includes an adhesive surface and a pull tab, wherein the adhesivesurface secures the vent hole cover over the vent hole.
 5. The chestwound seal of claim 1, wherein the chamber further includes a secondvent channel extending radially outward from the central portion of thechamber, wherein the flexible sheet includes a second vent hole alignedover the second vent channel.
 6. The chest wound seal of claim 5,wherein the chamber further includes a third vent channel and a fourthvent channel extending radially outward from the central portion of thechamber, wherein the flexible sheet includes a third vent hole alignedover the third vent channel, and a fourth vent hole hold aligned overthe fourth vent channel.
 7. The chest wound seal of claim 1, wherein thevent channel extends a length from a center of the chamber to aterminus, wherein a shape of the terminus of the vent channel isapproximately semi-circular.
 8. The chest wound seal of claim 1, whereina diameter of the vent hole is approximately one-fourth of an inch. 9.The chest wound seal of claim 1, wherein a length from a center of thechamber to a center of the vent hole is in the range of one to two and ahalf inches.
 10. The chest wound seal of claim 9, wherein the lengthfrom the center of the chamber to the center of the vent hole is in therange of one and one fourth inches to two inches.
 11. The chest woundseal of claim 10, wherein the length from the center of the chamber tothe center of the vent hole is approximately one and a half inches. 12.The chest wound seal of claim 1, wherein the minimum hydrogel width isone-half inch or greater.
 13. The chest wound seal of claim 12, whereinthe minimum hydrogel width is approximately one-inch.
 14. The chestwound seal of claim 12, wherein the vent channel is approximatelythree-fourths of an inch wide.